Optional Accessories : MTC-25V: For vertical columnar orientation of up to 3 loudspeakers extension of the woofer surround that MTC-25/23H: For horizontal splaying of two speakers. Three brackets array up to six loudspeakers in a 360? array. MTC-28/25CM: Ceiling-mount adapter. MThe Control 25AV can be used full range or low frequencies can be further